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Par Collection Par Auteur Par Date Par Sujet Par Titre
  • Tools and cover effects in bedload transport observations in the Pitzbach, Austria
  • tools and cover effects are active on the channel bed. Dependent on the local balance between sediment supply and transport capacity, either effect may be dominant at different locations along the cross-section at the same time. These observations may
  • have implications for modelling of bedrock erosion in landscape evolution models and of bedrock channel morphology. Erosion models that do not incorporate both tools and cover effects are not sufficient to describe observations. The changing balance
  • 2009
  • Assessing the effect of vegetation-related bank strength on channel morphology and stability in gravel-bed streams using numerical models
  • Bank strength due to vegetation dominates the geometry of small stream channels, but has virtually no effect on the geometry of larger ones. A rational regime model is used to explore the scale effects: it parameterizes vegetation-related bank
  • strength using a dimensionless effective cohesion, Cr. The analyses show that the effect of vegetation on both downstream hydraulic geometry and the meandering-braiding threshold is strongest for the smallest streams in a watershed, but that the effect
  • 2009
  • Effects of rainfall change on water erosion processes in terrestrial ecosystems : a review
  • In this paper, the characteristics of changes in natural rainfall, its role on terrestrial ecosystems, the challenges, and its effect on surface water erosion dynamics are elaborated and discussed. The major priorities for future research are also
  • 2009
  • The geographical effects of the NAFTA on Canadian provinces
  • Canada ; Free trade ; Induced effect ; International trade ; Regional economy ; Spatial differentiation ; Trade agreement ; United States of America
  • 2009
  • Regional financial development and bank competition : effects on firms' growth
  • 2009
  • Effects of terrain smoothing on topographic shielding correction factors for cosmogenic nuclide-derived estimates of basin-averaged denudation rates
  • One important issue that has yet to be addressed is the effect of the accuracy and resolution of terrain representation by a digital elevation model (DEM) on topographic shielding correction factors. Topographic metrics scale with the resolution
  • of the elevation data, and terrain smoothing has a potentially large effect on the correction of terrestrial cosmogenic nuclide production rates for skyline shielding. For rough, high-relief landscapes, the effect of terrain smoothing can easily exceed analytical
  • errors, and should be taken into account. Here the AA. demonstrate the effect of terrain smoothing on topographic shielding correction factors for various topographic settings, and introduce an empirical model for the estimation of topographic shielding
  • 2009
  • Sedimentation effects of the Dongting Lake Area
  • According to a long series of measured sediment data, the sedimentation effects of the Dongting Lake Area (DLA) were studied in light of the relationship between sedimentation characteristics and resources and environment. The result shows
  • that the long-term deposition and the impact of human activities have led to a cycle of the evolution of sedimentation pattern, resulting in sediment disaster effects and resources effects in the DLA. The main features are presented. They will help to develop
  • 2009
  • Environmental effects of drainage, drain-blocking and prescribed vegetation burning in UK upland peatlands
  • Peatlands are important ecosystems for carbon (C) storage, provision of water resources and biodiversity. This paper reviews the hydrological, physicochemical and ecological effects of 3 widespread UK peatland management practices, namely artificial
  • drainage, drain blocking and rotational heather burning. Relatively little is known about the environmental effects of rotational heather burning compared with drainage and drain-blocking management, and for all three of these management techniques
  • there is scarce information on river ecosystem response. The AA. hypothesize some likely effects of basin-scale drainage, drain blocking and heather burning on stream ecosystems and illustrate these with a schematic model. Such a holistic consideration of peatland
  • 2009
  • Effect of particle density and inflow concentration of suspended sediment on bedload transport in rill flow
  • Laboratory flume experiments were carried out to evaluate the effect of particle density on bedload transport of sand-sized particles and the effect of a suspended load of clay particles (kaolinite) on bedload transport of sand-sized particles
  • but the effect of particle density on transport rates was much less important than flow discharge. Velocity measurements of clear flow, flow mixed with coarse particles and coarse particles confirmed the existence of a differentiation between suspended load
  • 2009
  • Prescribed-fire effects on rill and interrill runoff and erosion in a mountainous sagebrush landscape
  • Changing fire regimes and prescribed-fire use in invasive species management on rangelands require improved understanding of fire effects on runoff and erosion from steeply sloping sagebrush-steppe. The study area is located in the Reynolds Creek
  • and unburned sites and to evaluate surface-soil and vegetation factors that influence persistence of post-fire effects over a 3-year period. The data demonstrate that the persistence of fire effects on steeply-sloped, sandy sagebrush sites depends on the time
  • 2009
  • Carbon accumulation in Umbrisols under Quercus pyrenaica forests : effects of bedrock and annual precipitation
  • The aim of this study was to determine the effect of bedrock, mean annual precipitation (MAP) and slope orientation (SLO) on soil C accumulation under deciduous forests on the Sierra de Gata Mountains in the Central Iberian Massif (central western
  • 2009
  • Effects of a vermicompost composted with beet vinasse on soil properties, soil losses and soil restoration
  • The aim of this study was to evaluate the effects of beet vinasse composted with a vermicompost as a bulking agent on physical, chemical and biological properties of a soil located in a semi-arid Mediterranean ecosystem, and their potential
  • 2009
  • Effects of land use and land cover on sheet and rill erosion rates in the Tigray highlands, Ethiopia
  • The AA. conducted runoff plot experiments in the semi-arid north Ethiopian Tigray highlands to investigate whether erosion rates are within the same order of magnitude as the rates observed in central, east and south Ethiopia, to measure the effects
  • 2009
  • Area of attraction ; Induced effect ; Peripheral region ; Poland ; Regional development ; Rzeszów ; Town ; Urban function
  • system, a zone of strongest influence and metropolitan effects of Rzeszów was delimited. Next, the dynamics of change in the level of life and the level of development of municipalities in the zone as compared to other areas of the Podkarapackie region
  • were measured. Though as demonstrated by research results, within the area of strong spatial influence of Rzeszów positive spread effects dominate, metropolitan functions in the city’s hinterland are weakly developed. - (BJ)
  • 2009
  • Effects of the Alqueva Dam Reservoir on the distribution of steppe birds
  • The effects of the Alqueva Dam reservoir on the distribution of steppe birds (before and after flooding) was quantified using point-pattern analysis. Sampling points from the dam biological monitoring program, which included data from winter
  • 2009
  • Jobs deficits, neighbourhood effects, and ethnic penalties : the geography of ethnic-labour-market inequality
  • Employment ; England and Wales ; Ethnic group ; Human capital ; Local labour market ; Neighbourhood effect ; Social inequality ; United Kingdom
  • 2009
  • Government mobility : the power effects of the movement of detained asylum seekers around Britain's detention estate
  • 2009
  • Regional labor productivity in the Netherlands : evidence of agglomeration and congestion efects
  • 2009
  • The effects of female out-migration on Alaska villages
  • 2009
  • Effect of small-world networks on epidemic propagation and intervention
  • 2009